Cartridge Conversion Cartridge Question

[sirdutch]

I've recently acquired a conversion cylinder for my Pietta steel framed 1858 Remington, the kind without the gate.

I have some Miwell. 45 Colt Cowboy ammo with 250gr.with flat nosed round lead bullets. I figured on trying out my new cylinder soon but wanted to ask if it is safe. Standard pressure is around 14,000 for this cartridge but I haven’t found the pressure data on this particular cartridge made in Green Valley. California

Thanks for any help.

 

[AlexanderA]

Should be fine.

 

[Seedy Character]

The cylinder is .45 Colt?

Should be fine and fun. I would stick to Cowboy loads, though.

 

[sirdutch]

Thank you!

 

[gwpercle]

Cowboy Loads should be standard pressure as cowboy rules don't allow the use of +P ammo in that competition .
Does the box state a velocity or pressure ?
Gary

 

[CraigC]

Cowboy loads are typically about 200fps below standard pressure loads and well under maximum pressure. Probably more like blackpowder pressures of ~10,000psi.

 

[Driftwood Johnson]

You are not going to find pressure data on 45 Colt Cowboy Ammo anywhere, because there is no SAMMI Spec for 'Cowboy Ammo'. And no ammunition manufacturer is going to release pressure data anyway.

Here is part of the pamphlet that came with my R&D 45 Colt cartridge conversion cylinder, which is probably the same type of cylinder you have. Notice velocity is specified, but that is not an indication of pressure, as different powders can generate significantly different pressure with the same bullet at the same velocity.






This is my old EuroArms 1858 Remington with its 45 Colt cartridge conversion cylinder. I suspect yours is very similar, if not the same. I unusually shoot it with cartridges loaded with Black Powder, but I suspect Smokeless 45 Colt "cowboy Ammo" would be fine to shoot in it too.

 

[AlexanderA]

This is my old EuroArms 1858 Remington with its 45 Colt cartridge conversion cylinder.

Here is my Euroarms with the Howell 5-shot conversion cylinder. Also shown are two of the percussion cylinders.

Notice that the extra safety notches are on the side of the cylinder (thereby engaging the bolt). On the percussion cylinders, and on your 6-shot conversion cylinder, the safety notches are on the back of the cylinder (thereby engaging the nose of the hammer).



In this picture, we can see that the chamber walls of the 5-shot conversion cylinder are much thicker than the chamber walls of the 6-shot:

 

[45 Dragoon]

Sadly, the safety notches are over the chambers just like a 6 shot cylinder. That pretty much negates the "extra strength" feature of the 5 shot cylinder. Might as well have the extra chamber.

Mike

 

[1KPerDay]

Cowboy loads are what is intended. Go for it.

 

[hawg]

Sadly, the safety notches are over the chambers just like a 6 shot cylinder. That pretty much negates the "extra strength" feature of the 5 shot cylinder. Might as well have the extra chamber.

Mike

I thought the reasoning for the five shot cylinders was because six shot cylinders had to have the chambers bored on an angle.

 

[AlexanderA]

Sadly, the safety notches are over the chambers just like a 6 shot cylinder. That pretty much negates the "extra strength" feature of the 5 shot cylinder. Might as well have the extra chamber.

I have noticed that the safety notches (on the 5-shot cylinder) are milled shallower than the regular locking notches. Given that the chamber walls are thicker, this should be safe. But your point is well taken.

Another thing that I noticed is that, in the 5-shot cylinder, the cartridge rims are fully countersunk. As you can see in Driftwood's picture of the 6-shot cylinder, the rims are partially exposed. I don't know if this is a weakness, or not.

I thought the reasoning for the five shot cylinders was because six shot cylinders had to have the chambers bored on an angle.

That's true, indirectly. The boring of the chambers at an angle was a feature that had been patented by Howell. When he sold the patent rights, he could no longer use that feature. To continue making conversion cylinders, he had to bore the chambers straight. Therefore the 5-shot design. The extra strength (if, indeed, it is that) was just a byproduct.

Anyway, I feel more confident in the strength of my 5-shot than I would with a 6-shot. But another factor is the strength of the host pistol. I have these conversion cylinders both for my Euroarms (Armi San Paolo, pictured above) and my Uberti NMA '58. The Uberti is more robust in every way. Given a choice, I would prefer to use a conversion cylinder in the Uberti rather than the Euroarms.

 

[45 Dragoon]

AlexanderA, if the safety notches are shallower than the locking notches then I would agree with you ( I've never seen one with that feature). Even better would be the gated conversion Howell sells ( or Kirst). That gives you full support (conversion ring/plate) for the cartridge during firing.
But, I understand the ease of a drop cyl and not wanting to modify the frame.

Mike

 

[Jim Watson]

this particular cartridge made in Green Valley. California

What ammo company is in Green Valley, California?

 

[Driftwood Johnson]

I thought the reasoning for the five shot cylinders was because six shot cylinders had to have the chambers bored on an angle.

That is correct.

The distance from the center of the cylinder to the bore on the 1858 Remington is too small to allow six 45 Colt cartridges to seat without their rims interfering with each other.

So Howell bored the chambers at a very slight angle so that the rims could clear each other. Yes, he patented the idea.

Later he sold the patent so when he started a new company to make cartridge conversion cylinders he could no longer make angled chambers without violating the patent.

So, for a while, Howell's 45 Colt conversion cylinders for the 1858 Remington only had five chambers.

More recently, the patent has expired, and Howell is once again making 45 Colt cartridge conversion cylinders with six angled chambers.

https://www.howellarms.com/1858-remington

As you can see in Driftwood's picture of the 6-shot cylinder, the rims are partially exposed. I don't know if this is a weakness, or not.

I actually had a gunsmith open up the counterbores on this cylinder ever so slightly to accommodate the slightly larger rim diameters of 45 Schofield cartridges. Schofield rims are about .520 in diameter, 45 Colt rims are about .512 in diameter.

Before he did so we mocked up the cuts on AutoCad and it became obvious that only opening up the diameter of the counterbores would leave a wafer thin area of steel between the counterbores and the outside of the cylinder. So we milled straight across to create 'viewing windows' that can be used to see if there is a cartridge in the chamber or not.









This later became a feature on the 45 Colt conversion cylinders being made by the company that supplies them to Taylors. If you check out Howell's website, he is doing the same thing now.



Why in the world would this be any weaker than a typical Single Action Army cylinder that leaves the entire rims exposed?

Remington 1858 with 45 Colt cartridge conversion cylinder showing rims visible in 'viewing windows":






Colt SAA with rims visible. This is in fact the way one can see if there is an empty chamber under the hammer. This one is fully loaded with six rounds.

Anyway, I feel more confident in the strength of my 5-shot than I would with a 6-shot. But another factor is the strength of the host pistol. I have these conversion cylinders both for my Euroarms (Armi San Paolo, pictured above) and my Uberti NMA '58. The Uberti is more robust in every way. Given a choice, I would prefer to use a conversion cylinder in the Uberti rather than the Euroarms.

That argument does not hold any water. It may make you more comfortable, but I have said many times that the cylinder, not the frame, is the pressure vessel in a revolver. As long as both revolvers have steel frames, it does not matter that the Uberti is slightly larger than the EuroArms (Armi San Paolo). I have both, my old EuroArms 1858 that I bought way back in 1975, and a stainless Uberti 1858 that I bought used a number of years ago. The Uberti came with a cartridge conversion cylinder just like the one I use in my old EuroArms 1858. It does not matter that the Uberti is slightly larger than the old EuroArms. Yes the conversion cylinder for the stainless Uberti is blued. Who cares? I don't.

Even better would be the gated conversion Howell sells ( or Kirst). That gives you full support (conversion ring/plate) for the cartridge during firing.
But, I understand the ease of a drop cyl and not wanting to modify the frame.

Which is exactly why I went with the R&D style conversion cylinders all those years ago. No alteration of the frame necessary. I can pop the original C&B cylinders back in and they are C&B revolvers again.

 

[Jim Watson]

So Howell bored the chambers at a very slight angle so that the rims could clear each other. Yes, he patented the idea.

I read an article in an English publication - The Handgunner, Ltd. - about the curious collector who wondered how a SAA could handle .455 Webley and .476 Enfield rim diameters. He made a connection with Rolls Royce and their toolroom guy measured and found angle bored chambers. This seems to not have been previously appreciated or widely known, so the "prior art" slipped by on the Howell cylinder.

 

[CraigC]

Which is exactly why I went with the R&D style conversion cylinders all those years ago. No alteration of the frame necessary. I can pop the original C&B cylinders back in and they are C&B revolvers again.

You can do the same thing with a gated conversion. You just have a really big capping cutout.